This study is a prospective, multicenter, non-randomized controlled trial, planning to enroll 180 patients with pure native aortic regurgitation. On the basis of standardized medical therapy, patients will be assigned in a 1:1 ratio to undergo transfemoral transcatheter aortic valve replacement (TF-TAVR) . This prospective, multicenter trial aims to evaluate the safety and effectiveness of transfemoral TAVR using the VitaFlow™ self-expanding valve system compared to dedicated transcatheter devices in patients with PNAR.

The primary endpoint is a composite of all-cause mortality, disabling stroke, and rehospitalization for heart failure, myocardial Infarction, and requiring dialysis or valve reoperation at 12 months post-procedure.

Secondary endpoints include procedure-related complications, long-term clinical events, patient functional status and quality of life, bioprosthetic valve imaging follow-up, echocardiographic parameters, and treatment costs. All endpoint definitions conform to the Valve Academic Research Consortium-3 (VARC-3) criteria

The purpose of this study is to evaluate the safety and efficacy of TF-TAVR for the treatment of isolated aortic regurgitation. The study will compare all-cause mortality, cardiovascular mortality, stroke, rehospitalization for heart failure, and renal failure requiring dialysis treatment at 12 months after TAVR. Additionally, the study will assess the incidence of hypoattenuated leaflet thickening (HALT) and reduced leaflet motion (RLM) via CTA, as well as the aortic valve root-prosthesis coaxiality. Changes and differences between groups in the following parameters will be evaluated using transthoracic echocardiography at 6 and 12 months after enrollment: left ventricular ejection fraction (Simpson method), left ventricular end-diastolic volume index (LVEDVi), left ventricular end-systolic volume index (LVESVi), left ventricular end-diastolic diameter (LVEDd), left ventricular end-systolic diameter (LVESd), estimated aortic valve orifice area, valvular regurgitation, and transvalvular pressure gradient compared with baseline. The study will also compare changes and differences between groups in the Minnesota Living with Heart Failure Questionnaire, Social Support Rating Scale (SSRS), International Physical Activity Questionnaire (IPAQ), and 6-minute walk test (6MWT) at 6 and 12 months after enrollment compared with baseline. Furthermore, the study will compare surgical costs, potential complication costs, and disease-related costs between the two groups.

Inclusion Criteria Age ≥ 60 years. Symptomatic moderate-to-severe or greater isolated aortic regurgitation.

Asymptomatic moderate-to-severe or greater isolated aortic regurgitation meeting at least one of the following criteria:

LVEF ≤ 55% (measured by biplane Simpson's method); LVESD > 50 mm ; LVESDi > 22 mm/mm²； LVESVi > 45mL/m2 Anatomical suitability for TAVR as assessed by the heart team. Provision of written informed consent by the patient or their legal guardian, with agreement to the treatment plan and willingness and ability to comply with all required follow-up assessments.

Exclusion Criteria Incomplete coronary revascularization. Less than 30 days of guideline-directed medical therapy at maximally tolerated doses.

Life expectancy < 1 year. LVEF < 45%. eGFR < 30 mL/min/1.73m². Known allergy or contraindication to required medications (e.g., aspirin, clopidogrel, warfarin) or contrast media.

Any condition that precludes contrast-enhanced CT. Concurrent moderate-to-severe or severe valvular heart disease other than aortic regurgitation.

Poor patient compliance, unable to complete follow-up as required. Any other condition that, in the investigator's judgment, would make the patient unsuitable for the study.